Welcome to the Monastery. Not sure how new a newbie you are... so I broke it down a bit

my                               # declare the variables in the local 
+scope (guarantees you won't overwrite a variable already in use or ca
+pture a value already assigned)
($_configParam,$_paramValue)     # A list of variable names that you a
+re declaring, note that coma separated variables between parenthesis 
+are treated similarly to an array for assignment purposes
=                                # and as you declare them you assign 
+them a value
  split(                         # a Perl function that splits strings
+ on the basis of a regular expression
/\s*=\s*/                        # the regular expression to use in th
+e split. any number of space characters, followed by an equals sign f
+ollowed by any number of space characters
, $_                             #  The second part of the split state
+ment, the string to be split $_ is the default variable, you will see
+ it a lot.
, 2);                            #  Limit the split to 2 values, close
+ the call to split and terminste the line with a semi-colon
$configParamHash{$_configParam}  # in an indexed list keyed on the par
+ameter name
= $_paramValue;                  # assign the value above to a hash en
+try keyed on the parameter name
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This is a common pattern used when reading through a configuration file to assign name value pairs in the file to an easily accessed indexed list.